/*
 * Copyright 2002-2021 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      https://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.springframework.graphql.web;

import org.reactivestreams.Publisher;
import reactor.core.publisher.Flux;
import reactor.core.publisher.Mono;

import static org.assertj.core.api.Assertions.assertThat;

public class ConsumeOneAndNeverCompleteInterceptor implements WebInterceptor {

	@Override
	public Mono<WebOutput> intercept(WebInput webInput, WebGraphQlHandler next) {
		return next.handle(webInput).map((output) -> output.transform((builder) -> {
			Publisher<?> publisher = output.getData();
			assertThat(publisher).isNotNull();
			builder.data(Flux.from(publisher).take(1).concatWith(Flux.never()));
		}));
	}

}
